Improvement in wood-bending machines



i UNITED STATES PATENT OFFICE.

ADAM LUCKHAUPT, OF COLUIIIBUS, OHIO.

IMPROVEMENT IN WOOD-BENDING MACHINES.

sired and with the least possible strain of the material.

Figure l is a perspective View of a machine embodying my improvement. Fig. 2 is a detached View of a bent telly with its conning belt and stretcher; and Fig. 3 details hereinafter described.

A post A of the machine-frame has attached firmly to its front orvertical portion a short semi-cylindrical block B, called the form The attachment of the form is by pin i) and key b', so as to enable the substitution of' dift hferent sizes of forms.

O is a clamp-block, adapted to be elevated or depressed by means of jack D. Fastened at its mid-length to the clamp C is a strap E of wrought-iron or other suitable metal. There are attached to this strap E, near each end, a

` lower pair of cheeks F F and an upper pair of cheeks G Gr. Hinged to the cheeks F F is a Wooden spring H, projecting inward beneath the strap, and a bell-crank rectangular or L-shaped arn`1 I J, whose longer limb I projects outward beyond the strap, and whose short limb .I is bifurcated and projects unward, each portion being slotted toreceive pins lo 7c', which project from a block K through slots in the cheeks G G.

L L are keys, which being withdrawn the studs'M M on cheeks GG may be shifted from one to another set of holes N N (see Fig. 3) for dierent lengths of stuit. Side clamps composed of cheeks O O and set-screws P enable the stuff to be secured to its place on the strap and prevent lateral displacement.

Q, is a stretcher, its ends forming a contin nation of the periphery of the form.

R is a key whose withdrawal enables the removal of the bent felly, with its band and stretcher, from the form.

S is the band or inner strap, having lips T and pins U.

V is a shackle whose hooked extremities are made to engage over the pins U. A screw m, which projects from the top of the stretcher Q through the middle link of the shackle V, receives a nut above said shackle, which nut, on being screwed down, acts to tighten and secure the felly and draw its ends together, when by Withdrawal of key R it can be removed. (See Fig. 2.)

Cords .t extend from the extension of long limbs I of arms I .I to a suitable windlass Y, and enable the drawing together of the arms, so as to apply the strap closely to the outside of the band and to bend the stuff from its mid-length outward. Other cords Z extend from the inner ends of the wooden springsH and pass around shafts I, to which weighted cords 2, being attached, act to hold the inner ends of the wooden springs firmly against the strap E, so that as the bending of the strap operation advances the wooden spring becomes bent and more and more closely applied to the back of the strap E'and hugs the latter closely throughout the entire length of the said spring as the bending reaches completion, so as to effectually prevent the usually great tendency of the stuft' to buckle out at the quarters On commencing the bending operation the first action of the L-shaped arms I .I is to press the blocks K inward, and by that means to clamp the ends of the stuff securely at the very start, but as the bending approaches completion the usual crippling of the ends of the timber is avoided in consequence of the ability of the blocks K to yield to any undue pressure outward.

I claim as new and of my invention hereinl. The use of a wood-bending form constructed in two parts, with one or more wedges or keys interposed, for the purpose of loosening from the stationary part of the form the movable part with the bent timber attached, substantially as hereinbefore explained.

2. In combination with a wood -bending strap E, the yielding blocks or abutments K, L-shaped arms I J, and cords 0c, or their equivalents, for the objects set forth.

3. In combination with a wood-bending stmp,the wooden springs H and tension-cords m and key R, substantially as and for the 0b- Z, arranged and operating substantially as jects stated. and for the objects stated. In testimony of which invention'I here- 4. The side clamps O O P, applied and 0punto setlny hand. etat-ing as set forth.-

5. In the described combination with pei'- manenbouter strap E and form B, or fheiiI Witnesses: equiva'lents, the detachable inner strap S, GEO. H. KNIGHT, stretcher Q, shackle V, and tightening-nut FRANCIS MILLWARD.

ADAM LUCKHAUPT. 

